3 mimimum modbus support requirements, Modbus, Communication – AERCO Modbus Communications Manual User Manual

Page 8: Gf-114

Advertising
background image

GF-114

MODBUS

Communication

Chapter 1

OMM-0035_0C

USER MANUAL

Introduction & Description

Page

8 of 200 AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 • Ph.: 800-526-0288 05/18/12

1.3 MIMIMUM MODBUS SUPPORT REQUIREMENTS

Implementation of a Modbus communication network utilizing the AERCO C-More Controller

and BMS/BMS II will be limited to the minimum support requirements listed in Table 1-1 which

follows. The remaining paragraphs in this Section provide more detailed descriptions for each

of the items listed.

Table 1-1: Modbus Communication and Support Requirements

CHARACTERISTIC

REQUIREMENT

Communication Medium:
EMS Master-To-BMS/BMS II/ACS Slave:
BMS/BMS II/ACS Master-To-C-More Slave:
EMS Master-To- C-More Slave:


RS232 (or RS485 With Optional Converter)
RS485, 2-Wire Differential Bus With Shield
RS485, 2-Wire Differential Bus With Shield

Allowable Cable Lengths:
RS232:
RS485:
PWM:


50 Feet, Maximum
4,000 Feet, Maximum
1,000 Feet, Maximum

Address Support From Master:
BMS/BMS II/ACS:
C-More Controller (Slave):

Broadcast Messages:


128 to 247 (From a Master EMS)
1 to 127 (From Master BMS/BMS II/ACS or

EMS)
Address 0 is Reserved for Broadcast

Messages

Transmission Mode Support

RTU (Remote Terminal Unit)

Timing Specifications:
Baud Rate:

Message Framing:



Character Framing:


Heartbeat Timeout:


Fixed at 9600 For C-More
Adjustable For BMS/BMS II/ACS: 2400, 4800,

9600, 14.4k, 19.2k

Default = 9600
Silent period of at least 3.5 character times

Before first character and After last character of

message
No more than 1.5 character times of silence

between received and transmitted characters
Fixed at 10 seconds For C-More

Adjustable For BMS/BMS II/ACS: 5 to 240

Seconds

Advertising